Next February, NASA’s will Mars probe will land in jezerro crater. Shortly after landing, it will begin collecting soil samples, which will return to earth for research in more than a decade. < / P > < p > however, scientists have a new worry that they will destroy any evidence of past life on Mars in Martian soil. The worry is acidic liquids. Acidic liquids that once flowed across the surface of Mars may have destroyed biological evidence hidden in the iron rich clay on the surface of Mars. The researchers conducted simulations involving clay and amino acids and came to their conclusion. < / P > < p > in the search for life on the red planet, its clay topsoil is the preferred collection target. Scientists say clay can protect organic molecules in it. However, the presence of acidic liquids on the surface in the past may affect the ability of clays to protect evidence of past life. The internal structure of clay is organized into layers, and evidence of biological life such as lipids, nucleic acids, peptides and other biopolymers may be captured and preserved, the researchers said. < / P > < p > under laboratory simulated Martian surface conditions, the researchers tried to preserve an amino acid called glycine in clays previously exposed to acidic liquids. After long-term exposure to ultraviolet radiation similar to that on Mars surface, the experiment showed that glycine molecules embedded in clay had photodegradation.

researchers found that exposure to acidic liquids would erase the interlayer space of clay and turn it into gel silica. The results show that when glycine is exposed to acidic liquid, the interlayer collapses and the organic matter cannot be preserved. The tests show why finding organic compounds on Mars is so difficult, the researchers said. Global Tech